Lesson 2

• What is the primary function of the autonomic nervous system?

  Homeostasis: the process by which the body maintains a constant and balanced internal state
• What are the two primary functions of homeostasis?

  1. A constant level of CO2 in the blood

  2. A constant body temperature- using functions like shivering, sweating and dilation
• What are the functions does the autonomic nervous system carry out to keep the body functioning properly?

  Controlling the release of hormones from glands, regulating vital muscles and internal organs
• What are the two divisions of the autonomic nervous system?

  Sympathetic nervous system and the parasympathetic nervous system
• What is the primary state of decemberetic nervous system?

  A state of physiological activity and stimulation, increasing energy
• What are some functions of the sympathetic nervous system?

  Increase heart and breathing rate, pupil dilation and digestion and saliva production inhibited
• What does the sympathetic nervous system prepare the body for?

  The fight or flight response
• What is the primary state of the parasympathetic nervous system?

  A state of physiological rest, producing the opposite effects to the sympathetic nervous system
• What does the parasympathetic nervous system prepare the body for?

  Rest and digest response which Returns the body to its resting state
• What are the key functions of the parasympathetic nervous system?

  Decreased heart and breathing rate, pupil constriction and digestion and saliva production stimulated
• Why is the fight or flight response key in human survival?

  It prepares the body to either defend itself or escape from a situation of threat or danger
• What does the sympathetic nervous system prepare the body for in a fight or flight situation?

  Prepare the body for a threat or stress
• Why does the sympathetic nervous system increase heart rate in a fight or flight situation?

  To get more blood to the muscles
• Why does breathing become faster and deeper in a fight or flight situation?

  To increase oxygen in the blood for aerobic respiration
• What happens as a result of the sympathetic nervous system diverting blood flow to vital organs?

  Digestion is reduced
• Why may pupils dilate in a flight of Fight situation?

  For better Vision
• What is the first step in the Fight of flight response?

  The brain detects a threat
• What is the hypothalamus's role in the brain in the fight or flight response?

  Identifies the threatening event and instructs this sympathetic nervous system to react
• Which glands are activated in the first step of the fight or response?

  The pituitary and adrenal
• What happens to the autonomic nervous system during the fight or flight response?

  It changes from its normal resting state(parasympathetic) to a state of stress (sympathetic state)
• What hormone is released from the adrenal glands into the bloodstream?

  The stress hormone adrenaline
• What are these changes designed to do?

  Help us confront the Threat or give us the energy to escape
• What does the increase in adrenaline produce?

  Several physiological reactions, particularly in the cardiovascular system, increasing heart rate and blood pressure
• What happens once the Threat passes?

  The parasympathetic Division Returns the body to a normal resting state. This is called the rest and digest response
• What happens during the rest and digest response?

  Digestion is simulated, making a person feel hungry or thirsty
• How long does it take for the body to return to its resting state?

  20 to 60 minutes
• What are other functions of the fight or flight response caused by the changes in the autonomic nervous system?

  Ears → auditory exclusion → focus solely on the sound of the threat

  Eyes → tunnel vision → focus solely on threat to get as much information as possible

  Liver → converts glycogen to glucose → more aerobic respiration

  Hands → shaking → example of the body warming up the muscles for action

  Muscles → tense → preparation for movement